Curriculum - Pericardium
Section  of a parietal pericardium showing the fibrous pericardium consisting of compact  layers of collagen bundles with a few small vessels and interspersed elastic  fibers and serosal pericardium consisting of a layer of mesothelial cells. 
In  Fibrinous pericarditis, the strands of fibrin are organized between the  parietal (fibrous pericardium) and the visceral pericardium (epicardium).  This image shows fibrinous strands over the  surface of atrial and ventricles giving the surface a coarse velvety  appearance.
Section  of a parietal pericardium with fibrinous pericarditis showing a layer of fibrin  with chronic inflammation and inconspicuous mesothelial lining.
Cardiopulmonary  block showing that the anterior portion of the pericardial sac has been removed.  This shows the pericardial cavity filled with clotted blood that obscures the  heart in a patient who died of cardiac tamponade secondary to a ruptured  anterior wall myocardial infarction.  
The  parietal pericardium is adherent to the heart with obliteration of the pericardial  space.  There are focal thickenings of  the pericardium and calcification in the segment covering the anterior left  ventricle.
Parietal  (fibrous) pericardium (bracket) with marked fibrosis.  The dense fibrous tissue is superimposed on  the fibrous pericardium. This patient had multiple episode of pericarditis.  There are fibroblasts and small capillary  sized vessels without inflammation or exudate.  
Pericardial  cyst are usually unilocular and are lined by mesothelial cells with a fibrous  wall and focal aggregates of lymphocytes.
Metastatic  adenocarcinoma and fibrinous pericardial exudate in a pericardial biopsy of a  patient with recurrent pericardial effusion.

